Variable drive apparatus



Dec. 20, 1960 w. BLYDENBURGH 2,964,971

VARIABLE DRIVE APPARATUS Filed May 29, 1956 3 Sheets-Sheet. 1

INVENTOR. WHLTER BLYDENBUREH Dec. 20, 1960 Y w. BLYDENBURGH' 2,964,971

VARIABLE DRIVE: APPARATUS Filed May 29, 1956 5 Sheets-Sheet 2 x HE 1 m.NY-'HAHA w lIIlllllllllmlllllllllllllll 3 HII R :sul E s Alun vx o h AEI IN V EN TOR.

A WFM-EP BLYDENBLIREH Wr/m M Dec. 20, 1960 w. BLYDENBURGH 2,954,971

VARIABLE DRIVE APPARATUS Filed May 29, 1956 3 Sheets-Sheet 5 INVENTOR.WF1 crap: BLYDENEUREH MMM /q ORNE Y States Pte VARIABLE DRIVE APPARATUSFiled May 29, 1956, Ser. No. 588,153

17 Claims. (Cl. 74-567) This invention relates to Variable driveapparatus. The invention has for one of its objects the provision of anovel mechanical ararngement wherein the thrust of one drive member,against a second drive member, is modified in response to the positionof the one member in relation to the second drive member, and whereinthe second member exerts the modifying iniluence. While not limitedthereto, the invention is herein described as embodied in lapparatus forwinding wire-like material on spools, and incorporating a novel camfollower arrangement according to the invention.

The foregoing and related objects are achieved in an embodiment of theinvention incorporating a mechanical assembly comprising Va cam, ya camfollower engaging the cam, and means includingvthe cam follower forvarying the displacement of said cam. As herein described, the cam andcam follower arrangement cooperate to provide, in the winding apparatus,`a wire winding drive which is readily adjustable to accommodate spoolsof different widths.

Fig. l is a partially cut-away side view of winding apparatus accordingto the invention;

Fig. 2 is a side view of the apparatus shown in Fig. l, but in adifferent operating position;

Fig. 3 is a sectional view taken 'through line 3 3 of Fig. l; andy Fig.4 is an illustration of lan adjustable Wedge cam according to anotheraspect of the invention.

In the manufacture of certain wire-like materials, such as grid-Wire forelectron tubes, the wire is usually wound on commercially ava-ilablespools. These spools have relatively high dimensional tolerances, thewidths of spools of a single spool type varying between relatively largelimits. This variation in spool width is often of the order of severaltimes the diameter of the wire to be wound. In such a case it isnecessary to adjust the width of the winding on as pool so that it willneither exceed the width of the spool nor fall short of the spool endand create a gap at the end. (When the wire falls into such gap, causedby an incomplete winding on an extra wide spool, the wire layers becometangled, resulting in kinks or a breakage of the Wire when it is drawnfrom the spool.) At the same time it is desirable that the windingapparatus be capable of adjustment, to accommodate spools of differentWidths, with a minimum of time and effort on the part of lan operatorwho positions the spool on its spindle. The problems Iaforementioned are`solved in the apparatus to be described.

Fig. l illustrates winding apparatus of the invention as embodied in laWire spooling machine of the type adapted to wind relatively fine wireon a spool 12. The machine comprises a frame in the form of a base 14having at one end thereof (-at the right side of Fig. l) a bracket 16which supports a wire guiding reel 18. The other end of the base 14 isprovided with a second bracket 20 in the upper end of which is journaleda shaft 22 to be described. Finally, there is fixed to the base 14 three2,964,971 liatteritedA Dec. 210, 1960 rice 2 guide wheels 24, 26, and 28for supporting and guiding a winding mechanism 30 to be described.

The winding mechanism As shown in Figs. l, 2, and 3, the windingmechanism 30 comprises another frame in the form of a housing 32 havinga pair of tracks 3'4 and 36. The first track rolls on one guide Wheel 28and the other track 36 rollsY on two guide wheels 24 and 26. 'Themechanism 30 is consequently adapted to move in the directions indicatedby arrow A in Fig. 1.

The housing 32 has a pair of collars 38 and 40 in which are journaledthe shaft 22 aforementioned. The

shaft 22 is provided with a number of flange-like collars 46 remains xedinglooatio-n with respect to the base 14.-

To assure that the pulley 46 remains xed with respect to the base 14,the pulley `46 is maintained within two arms 5l) and 52 of the secondbracket 20 by means o f bearings 5'4 and 56. The pulley 46, and thus theshaft 22, is rotated by means of a belt 58 connected to a motor 60.

One end of the shaft 2.2 (the right end in Figs. 11 and 2) is adapted tosupport the spool 12 in a snug t thereon and thusY serves as a spoolspindle. The spool 12 is xed to the shaft 22, as by a nut 62, to assurethat the spool will rotate with the shaft. When the shaft 22 is rotated,say in direction B, Wire 10 from a wire source 64 is fed past the Wireguiding reel 18A and is wound on the spool 12.

In order to wind the wire 10 evenly along the spool 12, the spool 12 isreciprocated in -directions A to an extent equal to the distance betweenthe flanges 66 and 68 of the spool 12. This reciprocation will now bedescribed.

As shown in Figs. l and 3, the winding mechanism 30 has fixed thereto afirst drive member in the form of a cardioid cam 70, the cam beingmounted .on acam shaft 72' which is in turn journaled into the housing32. The cam 70 bears against a second drive member in the form of a camfollower 74 which is maintained substantially xed with respect to thebase 14. Actually, however, and 'as will be `described more fully in thefollowing, the cam follower 74 is mounted for small arcuate movements indirections D to supplement the movement of the cam 70 so as to increasethe range of movementA afforded by the engagement of `the cam with thecam follower.

The cam 70 is geared to the shaft 22 so that the shaft 22 makes apredetermined number of rotations'during each rotation of the cam 70.The gearing is shown here. in the form of a worm 76 and meshing wormgear 78.'

While a single worm drive has been shown for simplicity any equivalentgear box arrangement may be used to provide a readily changeable gearratio between the shaft and the cam. The worm gear '78 and the cam 70are each fixed to the cam shaft 72 so that the two rotate in unison withthe cam shaft 72. Since the worm' gear 78 meshes with the worm 76, thecam 70 will rotate once to provide a back and forth movement indirections A every time the worm 76, and thus the shaft 22, makes apredetermined number of rotations. If, for example, the worm 76 is ofthe single lead variety,-and the worm gear 718 is providedwith sixteenteeth, the cam 70` would make `one rotation through an arc of 360degrees for every sixteen rotations of the shaft 22. In such a case whenthe shaft 22 makes sixteen 360 degree rotations it is desirable that twolayers of wire be-wound on, the

spool, one layer of eight turns during the back movement and one layerof eight turns during the forth movement. In this situation the wire tobe wound would have a diameter approximately equalto 1/s of the distancebetween the two spool tlanges y66 and 68. In actual practice, however,the wire diameter may be of the order of one or two thousandths of aninch. This means that the ratio between the number of rotations of thecamv 70 and the shaft 22 `should be a few thousand to one.- In such acase an equivalent gear box reduction unit would be used instead of theworm and worm gear combination illustrated for simplicity.

In operation, the shaft 22is rotated by the motor 60. This causes wire10 to be wound on the spool 12. At the same time, the cam 70 rotates indirection C. The rotation of the cam 70 moves the winding mechanism 30in a direction to the right (Figs. 1 and 2) causing the wire 10 to beWound along the length of the spool core 80 (that is, along the width ofthe portion of the spool between the flanges 66 and 68).

Fig. 2 illustrates the position of the winding mechanism 30 when it has'reached the end of its travel in the direction to the right. It will benoted that the point 82 of the cam 70 is now in engagement with the camfollower 74. As the cam 70 continues to rotate in direction C, thewinding mechanism 30 is moved in an opposite direction, namely in adirection toward the left, by means of aspring 84 which is connectedbetween a portion of the housing 32 and a portion of the base 14.

The variable drive As has been mentioned before, the actual width of aspool is often different from its nominal width. The variable drivearrangement ofthe invention allows the Winding apparatus to beaccommodated to differences in spool widths. The throw of the cam 70 ischosen to be equal to less than the minimum distance, between the`flanges 66 and 68, which is expected to be encountered in any of thespools 12 to be wound. Thus, for example, if the average width of thespool winding is three inches (the distance between spool flanges 66 and68 being this distance), and the maximum variation in spool width isexpected to be plus or minus 1A inch, then the initial throw of the cam70 is adjusted to be not greater than 2% inches. The additional movementof the winding mechanism 30 will be made up by a movement of the camfollower 74 in direction D so as to provide, with the movement ofthe camfollower 74, a combined cam throw equal to the distance between the twoanges 66 and 68 of the spool 12.to be wound.

The cam follower 74 is mounted for rotation about a shaft 86. The shaft86, in turn, is fixed to an L-shaped arm `88 which is supported forrotation about a pivot 90 fixed with respect to the base 14. Theposition of the arm 88 with respect to the pivot 90 thus controls theposition of the cam follower 74.

The position of the arm 88, and thus the initial position of the camfollower 74, is determined by the following: A first adjusting screw 92,which is threaded through a portion of the arm 88 remote from the pivot90, extends through the arm 88 and contacts a plate 94. The plate 94 isxed to and extends from` the base 14. The iirst adjusting screw 92 isprovided with a knob 96 for ease of adjustment. Since the spring '84provides a pressure urging the cam 70 against the cam follower 7 4, thelower end of the iirst adjusting screw 92 is maintained in contactagainst a surface of the plate 94. The iirst adjusting screw 92, by anappropriate setting of the screw in the arm 88, controls the maximumtravel of the winding mechanism 30 in one direction, the direction totheleft. This position of maximum travel is used to determine the right end(in Figs. I1 and 2) of the wire winding on the spool core 80. Inpractice, when ya spool 12 is mountedon the spool holding end of theshaft 22, the cam 70 is moved to its position of least throw (in theposition illustrated in Fig. 1) and the lirst adjusting screw 92 isadjusted so that the end of the spool core adjacent to the right flange68 is in alignment with the wire guiding reel 18. Thus, by anappropriate setting of the knob 96 of the screw 92, the startingposition of the winding operation may be easily adjusted.

A second adjustment of the throw of the cam 70 is also provided. Thesecond adjustment controls the end position of the camv throw. Thissecond adjustment is used to determine the left end (Fig. 2) of the wirewinding on the spool core 80. To permit of this adjustment the arm 88 isprovided with a second adjusting screw 98 having a control knob 100.This second adjusting screw 98 is threaded into another portion of thearm 88 remote from the pivot 90. The second adjusting screw 98 bearsagainst a lever 102 which is also supported for rotation about pivot 90.In order to maintain the lever 102 in contact with the screw 98 a spring104 is connected at one end to a portion of the arm y88 adjacent to thesecond screw 98 and at the other end thereof to aportion of the lever102 adjacent to the screw bearing surface thereof. A second cam follower106 is lixed to the end ofthe lever 102 remote from the pivot 90. Thesecond camfollower 106 is adapted to engage a wedge cam 108 tixedtothe'base 14. When the second cam follower 106 engages the wedge cam 108the second cam follower is given a motion or displacement toward thefirst cam follower 74 (a clockwise motion in one direction D); Thismotion is transmitted to the second screw 98, by means of the lever 102,and moves the arm 88 clockwise in the aforementioned one direction D sothat the first cam follower 74 applies a force resulting in motion ofthe cardioid cam 70.

From the'foregoing it is seen that an appropriate setting of the rstknob 96 controls the maximum throw of the cardioid cam 70 in onedirection (the direction to the right) and determines the position ofthe reel 18 with respect to the spool 12 at the start of the windingopera tion; and thefsecond knob controls the throw of the cam 70 in theopposite direction (the direction to the left) anddetermines theposition of the reel with respect to the spool 12 when the wire 10reaches the first spool flange 66.

The sequence of steps in adjusting the knobs 96 and 100 will now beexplained. An empty spool 12 is mounted on the end of the shaft 22 andthe cam 70 is rotated to its position of least throw,A as illustrated inFig. l. The first knob 96 is then rotated until the starting end of thespool 12 (the end of the spool adjacent to the ange 68) is in line withthe wire guiding reel 18. The wire is then xed to the core 80 of thespool 12 as by being threaded through an aperture 110 in the spool 12and the wire winding operation is started. When the winding mechanism 30has moved the spool 12 to a position where the wire guiding reel 18 isadjacent to the other flange 66 of the spool 12, the second knob 100 isrotated to determine the maximum thrust of the cam '70 (Fig. 2). Whenthese two adjustments have been made, namely the adjustment of knobs 96and 100, the wire winding operation is continued until the spool 12 isfull. All of the layers of wire on the spool will have their position atthe end adjacent to one ange 68 determined by the setting of one knob 96and at the end of the winding adjacent to the other llange 66 determinedby the setting of the other knob 100.

In the winding apparatus of Figs. l to 3 the wedge cam 108, whichcontributes to the control over the motion of the first cam follower 74,has been described as fixed to the lower track 36 of the housing 32. Itwill be appreciated that the steepness of the slope of the wedge cam 108may itself be adjustable so as to give even ner control over the motionof the first cam follower 74 against the cardioid cam 70. Fig. 4illustrates one such adjustable wedge cam 112 useful in the windingapparatus of Figs. 1 to 3. The wedge cam 112 is hinged, as by a hinge114,

to the lower track 36 for movement in directions E. The slope of the cam112 is determined by the setting of Aa thumb screw 1-16 which isthreaded through a portion of the lower track 36 under the cam and bearsagainst a sur-v face of the cam 112 facing the track.

From the foregoing it is seen that the variable drive apparatus of theinvention contributes to a wire winding machine which is readilyadaptable to wire spools of different widths and which accommodatesthese different spools with a minimum of time and effort on the part ofan Operator.

While useful in the winding apparatus described, it is apparent that thevariable drive apparatus is also useful in other mechanisms having apair of drive members which cooperate to provide a single resultantmotion and where it is desirable to have the movement of one drivemember, against the other member, modified in response to the positionof the one member with respect to the other member.

What is claimed is:

1. A motion transfer device including a cam, mounted for rectilinear androtational movement a part to be moved, said cam engaging said part formovement therewith, a cam follower engaging said cam, said cam having ariser portion, said riser portion engaging said follower during aportion of a cycle of rotation of said cam and producing a displacementof the thicker portion of said cam in the direction of said follower,and rectilinear motion of said cam in a direction opposite to said firstnamed direction and means connected to said cam follower for impartingto said follower a component of motion in a` direction opposite thedirection of displacement of said cam in response to a portiononly ofthe rectilinear movement of said cam, said follower having a componentof motion in said direction in response to another portion of therectilinear movement of said cam, the magnitude of said displacement ofsaid cam being fixed and means for adjusting the magnitude of movementof said cam follower, whereby said part to be moved is given acumulative motion including the displacement of said cam and themovement of said cam follower during said another portion of therectilinear movement of said cam.

2. Motion imparting means comprising a cam, a cam shaft for said cam,and a cam follower engaging said cam, a support for said cam,said'support being movable with respect to said cam follower, means forurging said cam into engagement with said cam follower for transmittingmotion from said cam to said cam` follower, said cam being movable in alinear direction and means for moving said follower in said direction inresponse to a movement of said cam in said direction.

3. Motion imparting means comprising two members, a support for one ofsaid members, said support being movable with respect to the other ofsaid members, said one of said members comprising a cam and a cam shaftfor said cam, said other of said members comprising a cam followerengaging said cam, means urging said members into engagement fortransmitting motion from said one of said members to said other of saidmembers, said one of said members being movable in a linear direction,and means for moving said other of said members in said direction inresponse to a movement of said one member in said direction.

4. A mechanical assembly comprising a cam, a cam follower engaging saidcam, a cam shaft for said cam, said shaft responding in rectilinearmovement in a given direction away from said cam follower in response torotation of said cam, and a support for said follower, said supportbeing movable in said direction and in response to said movement formodifying the magnitude of said movement in said direction.

5. A mechanical assembly comprising two spaced cams, and a cam followerbetween said cams, said cam follower being adapted to engage one of saidcams, and power transfer means connecting said follower with the otherof said cams', said cams having a structure for imparting displacementshaving components in substantially opposite directions, said powertransfer means being mounted for transferring the displacement of theother of said cams to said one ofr said cams in response to the move'-ment of said one of said cams for modifying the displacement of said oneof said cams. Y

` 6. Variable'drive apparatus comprising a cam mounted for rotationabout an axis and for substantially rectilinear movement in a givendirection, and a cam follower mounted in cam follower contact againstsaid cam and for cam driving movementin said direction',r whereby theend motion of said cam in said direction is determined by the contour ofsaid cam and by the motionrof said follower in said direction, said camfollower being adjustable to provide a predetermined magnitude of camdriving movement, whereby said end motionk of said cam is through apredetermined distance.

- 7. Variable drive apparatus comprisingfirst and second frames mountedfor substantially rectilinear motion with respect to each other, a cammounted on said first:

frame for rotation about an axis fixed with respect to said first frame,a cam follower movably mounted on said second frame and in cam followerrelation with said carn, said cam follower being movable in apredetermined direction in response to rectilinear movement of said camin said direction, whereby the movement of said frames with respect toeach otheris determined by the contour of said cam and by the movementof said cam follower in said direction.

8. Variable drive apparatus comprising first and second frames mountedfor substantially linear motion in a given direction with respect toeach other, a cam mounted on said first frame for rotation about an axisfixed with respect to said first frame, a cam follower mounted on saidsecond frame in motion transfer relation with `said cam and adjustablefor movement in said direction, a' second cam mounted on said secondframe and having a varying dimension in a direction substantiallyvopposite to said given direction, a second cam follower ymountedbetween said cams and adapted to engage said second cam in motiontransfer relation therewith, and a motion transfer arm connecting saidcam followers for transferring the'` movement of said second cam to saidfirstcam in responsel to the movement of said frames with' respect to=each other, whereby the movement of said frames with respect to eachother is determined by thevc'ontourof said camy and by the position ofsaid cam follower in saiddirection; 9. Wire winding apparatus comprisingfirst and second frames mounted for linear rnotion with respectrto eachother, a spindle mounted on said first frame for linear movementtherewith and for rotation about an axis fixed with respect to saidfirst frame and adapted to support a spool, a substantially cardioid cammounted on said first frame for rotation about a second axis fixed withrespect to said first frame and connected to said spindle for linearmotion therewith, a wedge cam fixed to said second frame and having amotion imparting dimension substantially opposite that of said cardioidcam, a motion transfer structure pivoted on an axis fixed with respectto said second frame, a first cam follower mounted on said structure andengaging said cardioid cam in power transfer relation therewith, and asecond cam follower mounted on said structure and engageable with saidwedge cam for imparting movement to said first cam followersubstantially opposite that of said cardioid cam, said wedge cam andfirst and second cam followers being positioned to move said first camfollower in a direction opposite said motion imparting dimension of saidcardioid cam in response to the position of said spindle with respect tosaid second frame, whereby the linear movement of said spindle isdetermined by the lineal motion of said cardioid cam and the movement ofsaid first cam follower.

l0. A driving mechanism comprising a first driving member, a first meansconnected to said first driving member for driving the same, a seconddriving member, and a second means connected to said second drivingmember for driving the same, said first and second driving members beingin driving relation for transmitting motion from said second drivingmember to said first driving-member, said second means being actuated bysaidfirst driving member.

11; A motion imparting mechanism comprising a frame, a wedge shaped cammounted for movement with respect to said frame in one direction andhaving anvinclined surface for imparting movement in another direction,a lever assembly movable with respect to said cam and adapted to engagea part having an axisiixed with respect to said cam, said part beingadapted to be moved by said cam, said assembly including a motiontransfer structure having a cam fol-lower engageable with said surfaceto receive movement from said cam and to trans' mit said movement tosaid part to be moved in a direction substantially opposite said onedirection, whereby said part to be moved is subjected to a movement bysaid cam supplementing the movement of said part in said one direction.

12. A motion imparting mechanism comprising a structure including afixed support, an L-shaped lever having two arms, a rectilinear lever,one end of said rectilinear lever and one end of one of said arms beingpivotally mounted on said support for rotation on a common axis, saidL-shaped lever'having a junction portion of said arms adapted to engagea part to be moved in a rectilinear direction, a cam follower mounted onthe other end of said rectilinear lever, means adjustably fixed to theother arm of said L-shaped lever and engaging said fixed support at theend of a rotational movement of said L-shaped lever in one direction forstopping said movement, means adjustably fixed to said other arm of saidL-shaped lever and engaging said rectilinear lever, a cam movable withsaid part to be moved and engaging said cam follower during movement ofsaid part, said cam having a riser portion for moving said cam followerto rotate said rectilinear lever in a direction opposite said onedirection during movement of said part in said rectilinear direction,whereby said L-shaped lever is rotated in said opposite direction forsupplementing the movement of said part in said rectilinear direction.

13. A mechanical assembly comprising first and second spaced cams, a camshaft for said rst cam, a first cam follower engaging said rst cam and asecond cam follower engaging said second cam, a movable support and. axed support, said cam followers being mounted in spaced relation on saidmovable support, said movable provide a predetermined modification ofmovement of.

saidcam shaft.

l5. A mechanical assembly according to claim 13,V and wherein said firstcam is heart shaped, and said second cam is wedge shaped.

16. A variable drive apparatus comprising a movable support, a shaftmounted on said support, means restraining longitudinal movement of saidshaft with respect to said support, a cam shaft mounted on said supportand extending normal to said shaft, a cam fixed eccentrically to saidcam shaft, gears interconnecting said shaft and cam shaft, wherebyrotation of said shaft causes rotation of said cam shaft and cam, a camkfollower engaging said cam, a second support for said cam follower, andmeans for moving said second support in a direction axially of said rstnamed shaft when said movable support is moved in said direction.

17. A Variable drive apparatus according to claim 16 and wherein saidmeans for moving said second support includes a wedge shaped cam fixedto said movable support, a cam follower spaced from said rst named camfollower and engaging said wedge shaped cam, and a lever systemsupporting said cam followers and mounted on a xed pivot in a planeintermediate said cam followers.

References Cited in the tile of this patent UNITED STATES PATENTS Y1,199,105 Nuttall Sept. 26, 1916 1,592,060 Wilcox July 13, 19262,224,905 Franz Dec. 17, 1940 2,301,642 Roddy Nov. 10, 1942 2,533,094Cooper Dec. 5, 1950 2,574,775 Belcher Nov. 13, 1951 2,678,394 Curtis May11, 1954 2,759,367 Doutt Aug. 21, 1956 V2,771,250 Icenbice Nov. 20, 1956FOREIGN PATENTS 542,689 Germany Jan. 30, 1932

